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chen0040chen0040
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fix the bug with the eager prim
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‎README.md

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@@ -343,7 +343,7 @@ for(var i=0; i < mst.length; ++i) {
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### Use Eager Prim algorithm to find the minimum spanning tree of a weighted graph
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The sample code below show how to obtain the minimum spanning tree from a weighted graph using Eager Prim algorithm:
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The sample code below show how to obtain the minimum spanning tree from a weighted graph using Eager Prim algorithm (Link: [HTML DEMO](https://rawgit.com/chen0040/js-graph-algorithms/master/examples/example-eager-prim.html)):
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```javascript
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var jsgraphs = require('js-graph-algorithms');

‎examples/example-eager-prim.html

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<html>
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<head>
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<title>
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Minimum Spanning Tree Weighted Graph (Eager Prim)
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</title>
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<script src="../third-party-libs/vis/vis.js" type="text/javascript"></script>
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<script src="../src/jsgraphs.js" type="text/javascript"></script>
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<link href="../third-party-libs/vis/vis.css" type="text/css" />
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</head>
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<body>
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<h2>Minimum Spanning Tree Weighted Graph (Eager Prim)</h2>
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<div id="mynetwork"></div>
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<script type="text/javascript">
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(function(){
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var g = new jsgraphs.WeightedGraph(8);
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g.addEdge(new jsgraphs.Edge(0, 7, 0.16));
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g.addEdge(new jsgraphs.Edge(2, 3, 0.17));
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g.addEdge(new jsgraphs.Edge(1, 7, 0.19));
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g.addEdge(new jsgraphs.Edge(0, 2, 0.26));
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g.addEdge(new jsgraphs.Edge(5, 7, 0.28));
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g.addEdge(new jsgraphs.Edge(1, 3, 0.29));
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g.addEdge(new jsgraphs.Edge(1, 5, 0.32));
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g.addEdge(new jsgraphs.Edge(2, 7, 0.34));
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g.addEdge(new jsgraphs.Edge(4, 5, 0.35));
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g.addEdge(new jsgraphs.Edge(1, 2, 0.36));
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g.addEdge(new jsgraphs.Edge(4, 7, 0.37));
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g.addEdge(new jsgraphs.Edge(0, 4, 0.38));
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g.addEdge(new jsgraphs.Edge(6, 2, 0.4));
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g.addEdge(new jsgraphs.Edge(3, 6, 0.52));
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g.addEdge(new jsgraphs.Edge(6, 0, 0.58));
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g.addEdge(new jsgraphs.Edge(6, 4, 0.93));
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var prim = new jsgraphs.EagerPrimMST(g);
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var mst = prim.mst;
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var g_nodes = [];
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var g_edges = [];
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for(var v=0; v < g.V; ++v){
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g.node(v).label = 'Node ' + v; // assigned 'Node {v}' as label for node v
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g_nodes.push({
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id: v,
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label: g.node(v).label
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});
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}
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for(var i=0; i < mst.length; ++i) {
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var e = mst[i];
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var v = e.either();
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var w = e.other(v);
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e.highlighted = true;
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console.log('(' + v + ', ' + w + '): ' + e.weight);
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g_edges.push({
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from: v,
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to: w,
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length: e.weight,
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label: '' + e.weight,
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color: '#ff0000',
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value: 2
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});
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}
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for(var v = 0; v < g.V; ++v) {
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var adj_v = g.adj(v);
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for(var i = 0; i < adj_v.length; ++i) {
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var e = adj_v[i];
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var w = e.other(v);
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if(w > v) continue; // make sure only one edge between w and v since the graph is undirected
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if(e.highlighted) continue;
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g_edges.push({
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from: v,
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to: w,
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length: e.weight,
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label: '' + e.weight
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});
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};
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}
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console.log(g.V); // display 6, which is the number of vertices in g
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console.log(g.adj(0)); // display [5, 1, 2], which is the adjacent list to vertex 0
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var nodes = new vis.DataSet(g_nodes);
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// create an array with edges
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var edges = new vis.DataSet(g_edges);
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// create a network
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var container = document.getElementById('mynetwork');
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var data = {
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nodes: nodes,
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edges: edges
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};
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var options = {};
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var network = new vis.Network(container, data, options);
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})();
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</script>
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</body>
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</html>

‎src/jsgraphs.js

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@@ -899,14 +899,12 @@ var jsgraphs = jsgraphs || {};
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}
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this.mst = [];
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this.visit(G, 0);
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while(!this.pq.isEmpty() && this.mst.length < V-1) {
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while(!this.pq.isEmpty()) {
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var e = this.pq.minKey();
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var v = this.pq.delMin();
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var w = this.pq.delMin();
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this.mst.push(e);
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var w = e.other(v);
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if(!this.marked[w]){
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this.visit(G, w);
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}
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for(var i = 0; i < adj_v.length; ++i) {
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var e = adj_v[i];
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var w = e.other(v);
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if(this.marked[w]) continue;
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if(this.pq.containsIndex(w)){
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this.pq.decreaseKey(w, e);
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} else {

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